OHIO OUTDOOR NOTEBOOK

By Laura Jones, Ohio Department of Natural Resources
July 2004

Poison ivy: one souvenir of summer no one wants to bring home

Sharing the summer spotlight with baseball, hot dogs and mom’s apple pie, is that pesky plant of Ohio’s woodlands – poison ivy. For most of us, a chance encounter with the proverbial “leaves of three,” leaves most of us wishing we had let them be.

Most likely, many of us have childhood memories that include splotches of pink calamine lotion tattooed on our arms and legs. As adults, we are no less immune to those perils of poison ivy. In fact, if you enjoy playing in the outdoors, chances are good you’ll come in contact with some “itchy-ivy” before the end of summer.

Poison ivy does a good job of blending in with other leafy green plants. Except for its three leaves – and there are a lot of plants with that feature – this master of disguise can be difficult to identify because it grows like a ground cover, dwarf shrub and vine. That said, here are common traits you can look for when trying to spot poison ivy: a cluster of three leaves – two leaves growing opposite on the stem and a third at the top – that are pointy, ribbed and often shiny. Together they form a pyramid shape.

Native to North America, this plant is found in almost every natural setting in Ohio. Ironically, poison ivy isn’t even a true ivy, but a member of the cashew family. According to the experts, it is responsible for the most common plant allergies in the United States.

Poison ivy is a delicate plant containing a sticky sap known as urushiol oil (pronounced oo-roo-shee-ohl), which, oddly enough, isn’t poisonous at all. Yet once the oil gets on your skin, it binds with your own proteins, causing the immune system to attack the “intruder.” This allergic reaction is what causes the irritating rash, blisters, and itching.

But why does it seem that even if you never laid eyes on the offending plant, the presence of itchy, red bumps on your hands and arms say otherwise? It’s because urushiol sticks to everything – your clothes, the family pet, garden tools, and shoes – then unknowingly it gets transferred to your skin.

Some people believe that scratching spreads the rash, or that other people can “catch” it from your blisters, but that’s not so. Only the urushiol can cause the rash to spread. The fluid in blisters is manufactured by your own body and isn’t toxic.

It’s important to know that your allergic sensitivity to the sap changes over time. If you “caught” poison ivy when you were young, you might outgrow it as an adult. On the other hand, while it never bothered you as a child, as an adult you may seem to break out in a rash by just looking at the plant.

In addition to thriving in Ohio’s woodlands and fields, poison ivy can also be found growing in our yards. To remove this persistent plant from your landscape, you can use herbicides (carefully per instructions). Or, while wearing gloves, dig up every bit of the plant and carefully dispose of the pieces. Whatever you do, never burn poison ivy. Even the smoke carries urushiol, allowing it to get on your skin and into your lungs – not a very good thing.

In addition to being able to identify poison ivy, you can further reduce your risk of getting an itchy rash by minimizing your skin’s exposure. That means dressing defensively in long-sleeve shirts and pants and wearing gloves when gardening.

If you’ve been exposed to poison ivy, wash the affected area as soon as possible with lots of soap and water. You’ll also want to wash any clothing that might be carrying urushiol, including jackets, hats, shoes, camping accessories, etc. Remember to use care when handling those items to avoid getting the oil on your skin.

While poison ivy can drive us humans nearly crazy, wildlife remains completely unaffected by the plant’s oil. In fact, poison ivy is actually beneficial to wildlife as a food source. Waxy white berries appear in mid-summer and remain on the plant through the winter.

The berries are a coveted treat for many bird species because they’re rich in vitamins. Some of the birds that find poison ivy fruit delectable include flickers and other woodpeckers, sapsuckers, yellow-rumped warblers, thrushes, pheasants, quail, robins, catbirds, grosbeaks, and songbirds during fall migration. Many birds also catch bugs in the foliage, while small mammals and deer munch on the leaves and twigs.

Whether in the city or in the woods, don’t let the fear of poison ivy keep you from enjoying the outdoors this summer.

-30-